Our overall objective has been to elaborate and define the effects of UV radiation (300-380 nm) on the ocular lens particularly with respect to fluorogen generation in specific protein fractions. We have demonstrated two fluorogens as aging parameters in the lens and they account for much of the increasing yellow coloration of the aging lens nucleus and the formation of the brown nuclear cataract. These two fluorogens are associated with an increase in insoluble protein levels with age. These aging parameters (fluorogen and insoluble protein) can be accelerated in vivo and in vitro by exposing lenses to UV radiation and 3-aminotriazole. The specific lens protein fraction (or fractions) in which the fluorogens are generated will be extracted from normal and UV exposed human and rat lenses and nuclear cataracts, subjected to spectroscopic analysis (UV, fluorescence, EPR and Raman) and will be further broken down into their constituent peptides. The fluorescent peptides will be analyzed with respect to their amino acid content and sequence and the fluorogens will be extracted and purified and studied by IR and mass spectroscopy. One of the fluorogens is a photo-degradation product of tryptophan. This compound will be synthesized and compared with the extracted lens fluorogen by UV, fluorescence, IR and mass spectroscopy. We are continuing to develop a method for utilizing fluorescence spectroscopy in the intact eye so that one can monitor specific aging changes (fluorogen formation) in the living individual and the potential buildup of psoralens in the ocular lens in patients being treated with this compound for psoriasis. BIBLIOGRAPHIC REFERENCES: Lerman, S., Kuck, J., Borkman, R. and Saker, E., "Induction of an Aging Parameter (Fluorogen) in the Ocular Lens". Ann. Ophthal., in press, 1976. Lerman, S., Kuck, J., Borkman, R. and Saker, E., "Induction, Acceleration and Prevention (in Vitro) of an Aging Parameter in the Ocular Lens". Ophthalmic Res., in press, 1976.